1. Field of Use
This invention relates to circuit boards and more particularly to methods and circuit boards which facilitate fabrication of the various units of a data processing system.
2. Prior Art
Over the last fifteen years, integrated circuit (IC) technology has seen a change of four to five orders of magnitude in complexity. That is, such technology has gone from a single device on a chip to complexities of the order of tens of thousands of devices per chip. This has permitted computer manufacturers to offer a greater variety of hardware features to users at reduced cost.
However, while the advances made in integrated circuit technology has reduced the cost of incorporating such features into the various elements of a computer, the fabrication costs for such elements have increased.
For example, substantial cost reductions have been made in computer storage or memories as a consequence of the advances in integrated circuit technology. However, the inclusion of different types of error detection and/or correction circuits in addition to memory speed up, cache or fetch capabilities have necessitated manufacturers to provide a number of different types of memory units. This in turn has increased the number of different types of integrated circuit boards to be manufactured as well as increasing the number of integrated circuit chips normally included on a single circuit board. That is, computer manufacturers have provided for such options by developing different artworks for constructing types of circuit board designs for the number of possible combinations of options being offered. Others have reduced the number of circuit board designs by including several options on a single circuit board and connecting the circuits associated with only those options in use. While this has reduced fabrication costs, it has increased the number of integrated circuit parts required thereby increasing costs.
Accordingly, it is a primary object of the present invention to provide a technique and apparatus which facilitates the fabrication of the elements of a computer which include a variety of optional features.
It is a more specific object of the present invention to reduce the cost of computer units by minimizing the number of integrated circuit parts in constructing circuit boards including a number of optional features.